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The state department on Friday defended its decision to censor plans for a working, three-dimensional handgun that anyone can create from plastic with a 3D printer -- plans that have caused alarm among gun control advocates but were seen by some Second Amendment advocates as a breakthrough.

Plans for the gun were posted online this week by Cody Wilson, founder of Defense Distributed. More than 100,000 copies of the plans for the world's first 3D-printed handgun, The Liberator, were downloaded before it had its liberty taken away by the government.

Deputy spokesman Pat Ventrell confirmed Friday that the State Department has been in communication with Defense Distributed, suggesting that the existence of the plans may affect national security.

“We view [enforcing regulations on handguns] as an integral part of safeguarding U.S. national security and  furthering U.S. foreign policy objectives," Ventrell said during a briefing. "The U.S. is cognizant of the potentially adverse consequences of indiscriminate arms transfers, and therefore we strictly regulate export of defense items and technologies to protect our national interest.”

Wilson posted a note to his website Thursday evening announcing that he had been told not to distribute the files.

“[Defense Distributed's] files are being removed from public access at the request of the U.S. Department of Defense Trade Controls," read a banner atop the website. "Until further notice, the United States government claims control of the information.”

Wilson told FoxNews.com that he decided to comply with the request while he weighed his legal options.

"They asked that I take it down while they determine if they have the authority to control the info," he said. "It's clearly a direct response to everything we did this week. 3D printing is clearly not the best way to make an effective weapon."

Wilson says he has complied with most laws on the books and feels that the request from the Defense Trade Controls agency, a branch of the Department of State, may be politically motivated.

"If this is an attempt to control the info from getting out there, it's clearly a weak one," he said, adding that the CAD design for the weapon has already spread across the Internet at downloading sites like the Pirate Bay, which has taken over distribution of the files.

Ventrell said distribution the information was an act regulated by several national and international laws.

“Exports of non-automatic and semi-automatic firearms up to 50 caliber are controlled under the U.S. munitions list," he said. "In accordance with the Arms Export Control Act, any person who engages in the U.S. in the business of manufacturing or exporting defense articles, furnishing defense services, or engages in arms brokering covered by the International Traffic in Arms Regulations (ITAR), is required to register with the state department.”

All 16 parts of the controversial gun, called the Liberator, are made from a tough, heat-resistant plastic used in products such as musical instruments, kitchen appliances and vehicle bumper bars. Fifteen of the components are made with a 3D printer while one is a non-functional metal part which can be picked up by metal detectors, making it legal under U.S. law. The firing pin is also not made of plastic, though it is easily crafted from a metal nail.

The weapon is designed to fire standard handgun rounds and even features an interchangeable barrel so that it can handle different caliber rounds.

Defense Distributed is a not-for-profit group founded by Wilson, a law student at the University of Texas. He said the Liberator project was intended to highlight how technology can render laws and governments all but irrelevant.

"I recognize that this tool might be used to harm people," Wilson told Forbes. "That’s what it is -- it’s a gun. But I don’t think that’s a reason to not put it out there. I think that liberty in the end is a better interest."

His publishing of the printable blueprints online instantly sparked outrage in the U.S.

Using the file, anyone with access to a 3D printer could theoretically print the gun with no serial number, background check or other regulatory hurdles.

U.S. Rep. Steve Israel, D-N.Y., has already called for national legislation to ban 3D-printed guns.

"Security checkpoints, background checks and gun regulations will do little good if criminals can print plastic firearms at home and bring those firearms through metal detectors with no one the wiser," Israel said.

"When I started talking about the issue of plastic firearms months ago, I was told the idea of a plastic gun is science-fiction," he added. "Now that this technology is proven, we need to act now to extend the ban on plastic firearms."

Editor's Note: An earlier version of this story listed the Department of Defense as the source of the take-down request. It came instead from the Department of Defense Trade Controls, an arm of the Department of State. The corrected story is above.

Sky News contributed reporting to this story.